Multi-phasic ceramic composite

ABSTRACT

A ceramic composite can include a first ceramic phase and a second ceramic phase. The first ceramic phase can include a silicon carbide. The second phase can include a boron carbide. In an embodiment, the silicon carbide in the first ceramic phase can have a grain size in a range of 0.8 to 200 microns. The first phase, the second phase, or both can further include a carbon. In another embodiment, at least one of the first ceramic phase and the second ceramic phase can have a median minimum width of at least 5 microns.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority under 35 U.S.C. § 119(e) to U.S.Provisional Patent Application No. 62/332,162, filed May 5, 2016,entitled “MULTI-PHASIC CERAMIC COMPOSITE,” by Diana R. Tierney et al.,which is incorporated by reference herein in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to ceramic materials, and methods ofmaking composite ceramic materials, and more particularly to compositeceramic materials having a plurality of continuous phases.

BACKGROUND

A plurality of ceramic materials can be utilized in the formation ofdense multi-phase ceramic composite materials. The use of diverseceramic materials can cause delamination, cracking, and dimensionalissues. There exists a need for multi-phase ceramic composite materialsexhibiting improved properties.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated by way of example and are not limited in theaccompanying figures.

FIG. 1 includes a photograph of a conventional ceramic composite.

FIG. 2 includes a photograph of a ceramic composite according to anembodiment described herein.

FIG. 3A includes a cross-section image of a ceramic composite accordingto an embodiment.

FIG. 3B includes a digital reconstruction of the image of FIG. 3A.

FIG. 4 includes a perspective illustration of a portion of an armorcomponent in accordance with an embodiment.

FIG. 5 includes a cross-sectional illustration of a portion of an armorcomponent in accordance with an embodiment.

FIG. 6 includes a cross-sectional illustration of a portion of an armorcomponent in accordance with an embodiment.

FIGS. 7A to 7C include photographs of cross-sections of ceramiccomposites according to embodiments herein.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figures maybe exaggerated relative to other elements to help to improveunderstanding of embodiments of the invention.

DETAILED DESCRIPTION

The following description in combination with the figures is provided toassist in understanding the teachings disclosed herein. The followingdiscussion will focus on specific implementations and embodiments of theteachings. This focus is provided to assist in describing the teachingsand should not be interpreted as a limitation on the scope orapplicability of the teachings. However, other embodiments can be usedbased on the teachings as disclosed in this application.

The terms “comprises,” “comprising,” “can include,” “including,” “has,”“having” or any other variation thereof, are intended to cover anon-exclusive inclusion. For example, a method, article, or apparatusthat comprises a list of features is not necessarily limited only tothose features but may include other features not expressly listed orinherent to such method, article, or apparatus. Further, unlessexpressly stated to the contrary, “or” refers to an inclusive-or and notto an exclusive-or. For example, a condition A or B is satisfied by anyone of the following: A is true (or present) and B is false (or notpresent), A is false (or not present) and B is true (or present), andboth A and B are true (or present).

Also, the use of “a” or “an” is employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one, at least one, or the singular as alsoincluding the plural, or vice versa, unless it is clear that it is meantotherwise. For example, when a single item is described herein, morethan one item may be used in place of a single item. Similarly, wheremore than one item is described herein, a single item may be substitutedfor that more than one item.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples are illustrative only and not intended to be limiting. To theextent not described herein, many details regarding specific materialsand processing acts are conventional and may be found in textbooks andother sources within the ceramic arts.

The ceramic composite described herein can include a biphasic compositehaving a connectivity between phases that provides an increasedstability, meaning that delamination, cracking, and other dimensionalissues are reduced or prevented. Further, the unique microstructure ofthe ceramic composite can include wider phases than conventional ceramicproducts, as will be discussed in more detail below. Further, theceramic composite can exhibit high elasticity and high hardness, whichincreases the scattering of shock waves and makes the ceramic compositean improved ballistic armor material.

The ceramic composite can be a multi-phasic ceramic composite. Incertain embodiments, the multi-phasic ceramic composite product caninclude multiple phases including a first ceramic phase and a secondceramic phase arranged in an advantageous microstructure. Each of thefirst and second phase can be a continuous phase that extends from oneend of the ceramic composite to the other end.

Conventional microstructures of multi-phasic ceramic composites includefine grains dispersed throughout the cross-section, as illustrated inFIG. 1. By contrast, in certain embodiments, the ceramic compositedescribed herein or made according to the method described herein, canachieve a ceramic composite having a unique microstructure, referred toabove, as illustrated in FIG. 2. The unique microstructure can includeinterlocked phases comprising rows of directly adjacent ceramic grains.As used herein, the term “interlocked” refers to a configuration wherethe first and second ceramic phases are engaged with each other alongphase boundaries by overlapping or by the fitting together of theprojections and recesses of those phase boundaries.

When combining materials, in addition to selecting component phaseswhich have the desired properties, one must couple the component phasesto each other in an optimal manner. Connectivity of the individualphases is a critical parameter in ceramic composites designed for use asballistic protection because connectivity can affect the mechanicalproperties such as the ability to scatter shock waves. Each phase in aceramic composite may be self-connected in zero, one, two or threedimensions. For diphasic ceramic composites, there are ten possibleconnectivities: 0-0, 0-1, 0-2, 0-3, 1-1, 1-2, 1-3, 2-2, 2-3 and 3-3,where the first number in each pair indicates the number of dimensionsof connectivity for the first component phase of a diphasic ceramiccomposite and the second number in each pair indicates the number ofdimensions of connectivity for the second component phase of thatdiphasic ceramic composite.

For example, the 3-3 connectivity pattern denotes the number oforthogonal directions in which each phase is self-connected. In anembodiment, the ceramic composite can include at least a diphasicceramic composite having a 3-3 connectivity pattern. In the 3-3connectivity pattern, two phases form interpenetrating three-dimensionalnetworks, such as when the content ratio of the first phase to thesecond phase is in a range of 65:35 to 35:65, or in a range of 60:40 to40:60, or in a range of 55:45 to 45:55, or in a range of 52:48 to 48:52,or even a content ratio of 50:50, based on a total weight of the ceramiccomposite. In a further embodiment, the connectivity pattern may includea 1-3 connectivity pattern, such as when the content ratio of the firstphase to the second phase is in a range of 82:18 to 65:35 or 35:65 to18:82, or in a range of 80:20 to 65:35 or 35:65 to 20:80, or in a rangeof 78:22 to 65:35 or 35:65 to 22:78, or in a range of 76:24 to 65:35 or35:65 to 24:76, or in a range of 74:26 to 65:35 or 35:65 to 26:74, or ina range of 72:28 to 65:35 or 35:65 to 28:72, or in a range of 70:30 to65:35 or 35:65 to 30:70.

In certain embodiments, the phase boundaries can be controlled so as tohave a suitable median minimum width for each phase. A cross-section ofthe ceramic composite can be prepared for microscopic (e.g., scanningelectronic microscope (SEM) or optical microscope) analysis of themicrostructure and measurement of the median minimum width of differentphases of the ceramic composite. The cross-section can be polished to afinal surface finish achieved with a polishing agent including acompound rated at 0.01 μm (from Buehler) and a chemical or electricalbased etchant can be utilized to promote contrast at the phaseboundaries. When utilizing an SEM, the contrast can be achieved byutilization of a secondary backscatter detector. After preparation, thecross-section can be placed under a microscope with magnification of 50×to 1000×, 30 random fields can be selected, and each field is analyzedby using image analysis software, i-Solution DT-M (from IM Technology)according to the instructions provided by the software for determiningthe median minimum width of each phase of the ceramic composite. Aphotograph of a selected field can be taken and used as an originalimage for subsequent analysis. FIG. 3A includes an exemplary image of apolished and etched cross-section of a ceramic composite. After settingthe threshold for automated phase boundary detection, a digitalreconstruction of a phase can be generated on a pixel by pixel basis bythe software, based on the original image. FIG. 3B includes a digitalreconstruction of the phase in the darker color of the image of FIG. 3A.The threshold can be set such that the digital reconstruction of thephase can sufficiently match its original image as close as possible.For instance, by visual inspection, at least 90% of the phase in theoriginal image is captured by the digital reconstruction, and not morethan 10% of the neighboring phase is captured by the digitalreconstruction. After analyzing the area of the reconstructed phase, aminimum width of the field is calculated and provided by the software,and the median minimum width of the phase is the median value of theminimum width values from the 30 fields. In an embodiment, at least oneof the first ceramic phase and the second ceramic phase can have amedian minimum width of at least 4 microns, at least 5 microns, or atleast 10 microns, or at least 15 microns, or at least 20 microns, or atleast 25 microns, or at least 30 microns, or at least 35 microns. Inparticular embodiments, each of the first ceramic phase and the secondceramic phase can have a median minimum thickness of at least 20microns, or at least 25 microns, or at least 30 microns, or at least 35microns. In another embodiment, at least one or each of the firstceramic and second ceramic phases can have a median minimum thickness ofat most 200 microns, such as at most 180 microns, or at most 160microns, or at most 150 microns, or at most 140 microns, or at most 130microns. Further, at least one or each of the first ceramic and secondceramic phase can have a median minimum thickness in a range includingany of the minimum and maximum values noted herein, such as in a rangeincluding at least 4 microns and at most 200 microns. In a furtherembodiment, ceramic composites having different weight contents of firstphases and second phases can have similar median minimum thickness ofthe first phase and similar minimum thickness of the second phase.

In an embodiment, the first phase can be present in the ceramiccomposite in an amount of at least 1 wt %, or at least 2 wt %, or atleast 4 wt %, or at least 5 wt %, or at least 6 wt %, or at least 7 wt%, or at least 8 wt %, or at least 9 wt %, at least 10 wt %, or at least12 wt %, or at least 15 wt %, or at least 18 wt %, or at least 20 wt %,or at least 22 wt %, or at least 24 wt %, or at least 26 wt %, or atleast 28 wt %, or at least 30 wt %, or at least 32 wt % or at least 34wt %, or at least 36 wt %, or at least 38 wt %, or at least 40 wt %, orat least 42 wt %, or at least 44 wt %, or at least 46 wt %, or at least48 wt %, or at least 50 wt %, or at least 52 wt %, or at least 55 wt %,or at least 58 wt %, or at least 60 wt %, or at least 62 wt %, or atleast 64 wt %, or at least 66 wt %, or at least 68 wt %, or at least 70wt %, or at least 72 wt %, or at least 75 wt %, or at least 78 wt %, orat least 80 wt %, or at least 82 wt %, or at least 84 wt %, or at least86 wt %, or at least 88 wt %, or at least 90 wt %, or at least 92 wt %,or at least 94 wt %, or at least 95 wt %, or at least 97 wt %, or atleast 98 wt %, or at least 99 wt %, based on a total weight of theceramic composite. Further, the first phase can be present in theceramic composite in an amount of at most 99 wt %, at most 98 wt %, orat most 97 wt %, or at most 95 wt %, or at most 92 wt %, at most 90 wt%, or at most 88 wt %, or at most 85 wt %, or at most 82 wt %, or atmost 80 wt %, or at most 78 wt %, or at most 76 wt %, or at most 74 wt%, or at most 72 wt %, or at most 70 wt %, or at most 68 wt %, or atmost 66 wt %, or at most 64 wt %, or at most 62 wt %, or at most 60 wt%, or at most 58 wt %, or at most 56 wt %, or at most 54 wt %, or atmost 52 wt %, or at most 50 wt %, or at most 48 wt %, or at most 46 wt%, or at most 44 wt %, or at most 42 wt %, or at most 40 wt %, or atmost 38 wt %, or at most 36 wt %, or at most 34 wt %, or at most 32 wt%, or at most 30 wt %, or at most 28 wt %, or at most 26 wt %, or atmost 24 wt %, or at most 22 wt %, or at most 20 wt %, or at most 18 wt%, or at most 16 wt %, or at most 14 wt %, or at most 12 wt %, or atmost 10 wt %, or at most 8 wt %, or at most 6 wt %, or at most 4 wt %,or at most 2 wt %, or at most 1 wt %, based on a total weight of theceramic composite. Moreover, the first phase can be present in theceramic composite in an amount including any of the minimum and maximumpercentages noted herein. For instance, the first phase can be presentin the ceramic composite in an amount in a range of at least 1 wt % toat most 99 wt % or in a range of at least 8 wt % to at most 92 wt % orin a range of at least 10 wt % to at most 90 wt % or in a range of atleast 30 wt % to at most 70 wt %.

In an embodiment, the ceramic composite can include a silicon carbide.In a further embodiment, the total amount of silicon carbide present inthe ceramic composite can be at least 1 wt %, or at least 2 wt %, or atleast 3 wt %, or at least 4 wt %, or at least 5 wt %, or at least 6 wt%, or at least 7 wt %, or at least 8 wt %, or at least 9 wt %, or atleast 10 wt %, or at least 11 wt %, or at least 13 wt %, or at least 14wt %, or at least 15 wt %, or at least 17 wt %, or at least 18 wt %, orat least 20 wt %, or at least 22 wt %, or at least 24 wt %, or at least26 wt %, or at least 28 wt %, or at least 30 wt %, or at least 32 wt %or at least 34 wt %, or at least 36 wt %, or at least 38 wt %, or atleast 40 wt %, or at least 42 wt %, or at least 44 wt %, or at least 46wt %, or at least 48 wt %, or at least 50 wt %, or at least 52 wt %, orat least 55 wt %, or at least 58 wt %, or at least 60 wt %, or at least62 wt %, or at least 64 wt %, or at least 66 wt %, or at least 68 wt %,or at least 70 wt %, or at least 72 wt %, or at least 75 wt %, or atleast 78 wt %, or at least 80 wt %, or at least 82 wt %, or at least 84wt %, or at least 86 wt %, or at least 88 wt %, or at least 90 wt %, orat least 92 wt %, or at least 94 wt %, or at least 95 wt %, or at least97 wt %, or at least 98 wt %, or at least 99 wt %, based on a totalweight of the ceramic composite. Further, the total amount of siliconcarbide present in the ceramic composite can be at most 99 wt %, at most98 wt %, or at most 97 wt %, or at most 95 wt %, or at most 92 wt %, atmost 90 wt %, or at most 88 wt %, or at most 85 wt %, or at most 82 wt%, or at most 80 wt %, or at most 78 wt %, or at most 76 wt %, or atmost 74 wt %, or at most 72 wt %, or at most 70 wt %, or at most 68 wt%, or at most 66 wt %, or at most 64 wt %, or at most 62 wt %, or atmost 60 wt %, or at most 58 wt %, or at most 56 wt %, or at most 54 wt%, or at most 52 wt %, or at most 50 wt %, or at most 48 wt %, or atmost 46 wt %, or at most 44 wt %, or at most 42 wt %, or at most 40 wt%, or at most 38 wt %, or at most 36 wt %, or at most 34 wt %, or atmost 32 wt %, or at most 30 wt %, or at most 28 wt %, or at most 26 wt%, or at most 24 wt %, or at most 22 wt %, or at most 20 wt %, or atmost 18 wt %, or at most 16 wt %, or at most 14 wt %, or at most 12 wt%, or at most 10 wt %, or at most 8 wt %, or at most 6 wt %, or at most4 wt %, or at most 2 wt %, or at most 1 wt %, based on a total weight ofthe ceramic composite. Moreover, the total amount of silicon carbidepresent in the ceramic composite can include any of the minimum andmaximum percentages noted herein. For instance, the total amount ofsilicon carbide present in the ceramic composite can be in a range of atleast 1 wt % to at most 99 wt % or in a range of at least 10 wt % to atmost 90 wt % or in a range of at least 15 wt % to at most 85 wt % or ina range of at least 30 wt % to at most 70 wt %.

In an embodiment, the first ceramic phase can include a silicon carbide.The silicon carbide of the first phase can include α-SiC, 15R-SiC,3C-SiC, or any combination thereof. In an embodiment, the first phasecan include the silicon carbide in an amount of at least 50 wt %. Inanother embodiment, the silicon carbide can be present in the firstphase in an amount greater than 50 wt %, such as at least 52 wt %, or atleast 55 wt %, or at least 58 wt %, or at least 60 wt %, or at least 63wt %, or at least 65 wt %, or at least 67 wt %, or at least 68 wt %, orat least 70 wt %, or at least 72 wt %, or at least 75 wt %, or at least78 wt %, or at least 80 wt %, or at least 83 wt %, or at least 86 wt %,at least 88 wt %, or at least 90 wt %, or at least 91 wt %, or at least92 wt %, or at least 93 wt %, or at least 94 wt %, or at least 95 wt %,or at least 96 wt %, or at least 97 wt %, or at least 98 wt %, or atleast 99 wt %, or at least 99.1 wt %, or at least 99.2 wt %, or at least99.25 wt %, or at least 99.3 wt %, or at least 99.4 wt %, or at least99.5 wt %, or at least 99.6 wt %, or at least 99.7 wt %, or at least99.75 wt %, or at least 99.8 wt %, or at least 99.9 wt %, based on atotal weight of the first phase. In a further embodiment, the firstphase can include the silicon carbide in an amount of at most 99.99 wt%, or at most 99.95 wt %, or at most 99.92 wt %, or at most 99.9 wt %,or at most 99.8 wt %, or at most 99.75 wt %, or at most 99.7 wt %, or atmost 99.6 wt %, or at most 99.5 wt %, or at most 99.4 wt %, or at most99.3 wt %, or at most 99.25 wt %, or at most 99.2 wt %, or at most 99.1wt %, or at most 99 wt %, or at most 98 wt %, or at most 97 wt %, or atmost 96 wt %, or at most 95 wt %, or at most 94 wt %, or at most 93 wt%, or at most 92 wt %, or at most 91 wt %, or at most 90 wt %, based ona total weight of the first phase. In an embodiment, the first phase caninclude the silicon carbide in an amount in a range including any of theabove minimum and maximum percentages, such as in a range of 50 wt % to99.99 wt %, or in a range of 86 wt % to 99.99 wt %, or in a range of 88wt % to 99.95 wt %, or in a range of 90 wt % to 99 wt %.

In a particular embodiment, the silicon carbide present in the firstceramic phase can have a certain average grain size that can facilitateimproved formation and performance of the ceramic composite. Forinstance, the average grain size of silicon carbide in the first ceramicphase can be at least 0.3 microns, at least 0.5 microns, at least 0.8microns, such as at least 0.9 microns, or at least 1 micron, or at least1.2 microns, or at least 1.5 microns, or at least 1.8 microns, or atleast 2 microns, or at least 2.1 microns, or at least 2.3 microns, or atleast 2.5 microns, or at least 2.8 microns, or at least 3 microns, or atleast 3.1 microns, or at least 3.3 microns, or at least 3.5 microns, orat least 3.8 microns, or at least 3.9 microns, or at least 4.1 microns,or at least 4.3 microns, or at least 4.5 microns, or at least 4.8microns, or at least 5 microns, or at least 5.2 microns, or at least 5.3microns, or at least 5.5 microns, or at least 5.8 microns, or at least 6microns, or at least 6.2 microns, or at least 6.5 microns, or at least6.8 microns, or at least 7 microns, or at least 7.3 microns, or at least7.5 microns, or at least 8.1 microns, or at least 8.5 microns, or atleast 9 microns, or at least 9.3 microns, or at least 9.5 microns, or atleast 9.7 microns, or at least 10 microns, or at least 10.5 microns. Inanother particular embodiment, the average grain size of silicon carbidein the first ceramic phase can be at most 200 microns, such as at most190 microns, at most 180 microns, at most 175 microns, at most 170microns, at most 165 microns, at most 160 microns, at most 150 microns,at most 145 microns, or at most 140 microns, or at most 130 microns, orat most 125 microns, or at most 120 microns, or at most 110 microns, orat most 100 microns, or at most 95 microns, or at least 90 microns, orat most 80 microns. Moreover, silicon carbide in the first ceramic phasecan have an average grain size in a range including any of the minimumand maximum values noted herein. For instance, the first ceramic phasecan include silicon carbide having an average grain size in a rangeincluding at least 0.3 microns and at most 200 microns, or in a rangeincluding at least 1 microns and at most 200 microns, or in a rangeincluding at least 5 microns and at most 200 microns, or in a range of 1to 150 microns.

In these and other embodiments, the first phase can also include a boroncarbide, a carbon, or both. In an embodiment, the first phase caninclude boron carbide, carbon, or both, in an amount of at least 0.05 wt%, or 0.07 wt %, or at least 0.1 wt %, or at least 0.2 wt %, or at least0.25 wt %, or at least 0.3 wt %, or at least 0.4 wt %, or at least 0.5wt %, or at least 0.6 wt %, or at least 0.7 wt %, or at least 0.75 wt %,or at least 0.8 wt %, or at least 0.9 wt %, or at least 1 wt %, or atleast 1.2 wt %, or at least 1.4 wt %, or at least 1.5 wt %, or at least1.7 wt %, or at least 1.9 wt %, or at least 2 wt %, or at least 2.2 wt%, or at least 2.4 wt %, or at least 2.5 wt %, or at least 2.7 wt %, orat least 2.9 wt %, or at least 3 wt %, or at least 3.2 wt %, or at least3.4 wt %, or at least 3.5 wt %, or at least 3.7 wt %, or at least 3.9 wt%, or at least 4 wt %, or at least 4.2 wt %, or at least 4.4 wt %, or atleast 4.5 wt %, or at least 4.7 wt %, or at least 4.9 wt %, or at least5 wt %, or at least 5.2 wt %, or at least 5.5 wt %, or at least 5.7 wt%, or at least 5.9 wt %, or at least 6 wt %, or at least 6.4 wt %, or atleast 6.7 wt %, or at least 7 wt %, or at least 7.2 wt %, or at least7.5 wt %, or at least 7.7 wt %, or at least 8 wt %, or at least 8.4 wt%, or at least 8.7 wt %, or at least 9 wt %, or at least 9.2 wt %, or atleast 9.4 wt %, or at least 9.7 wt %, or at least 10 wt %, for the totalweight of the first phase. In another embodiment, the first phase caninclude a boron carbide, a carbon, or both, in an amount of at most 12wt %, or at most 11 wt %, or at most 10.5 wt %, or at most 10 wt %, orat most 9 wt %, or at most 8 wt %, or at most 7 wt %, or at most 6 wt %,or at most 5 wt %, or at most 4 wt %, or at most 3 wt %, or at most 2 wt%, or at most 1 wt %. In an embodiment, the first phase can include aboron carbide, a carbon, or both, in a range including any of the aboveminimum and maximum percentages, such as in a range of 0.05 wt % to 12wt %, or in a range of 0.07 wt % to 11 wt %, or in a range of 0.09 to10.5 wt %.

For example, in a particular embodiment, the first phase can includeboron carbide. Boron carbide can be present in the second phase in anamount of at most 10 wt %, such as at most 9.8 wt %, or at most 9.5 wt%, or at most 9.2 wt %, or at most 9 wt %, or at most 8.8 wt %, or atmost 8.5 wt %, or at most 8.2 wt %, or at most 8 wt %, or at most 7.8 wt%, or at most 7.5 wt %, or at most 7.3 wt %, or at most 7.2 wt %, or atmost 7 wt %, at most 6.8 wt %, or at most 6.5 wt %, or at most 6.3 wt %,or at most 6 wt %, or at most 5.8 wt %, or at most 5.5 wt %, or at most5.2 wt %, or at most 5 wt %, or at most 4.8 wt %, or at most 4.5 wt %,or at most 4.2 wt %, or at most 4 wt %, or at most 3.8 wt %, or at most3.5 wt %, or at most 3.2 wt %, or at most 3 wt %, or at most 2.8 wt %,or at most 2.5 wt %, or at most 2.2 wt %, or at most 2 wt %, or at most1.8 wt %, or at most 1.5 wt %, or at most 1.2 wt %, or at most 1 wt %,or at most 0.9 wt %, or at most 0.8 wt %, or at most 0.7 wt %, or atmost 0.6 wt %, or at most 0.5 wt %, or at most 0.4 wt %, or at most 0.3wt %, or at most 0.25 wt %, or at most 0.2 wt %, or at most 0.1 wt %,based on a total weight of the first phase. In another particularembodiment, the first phase can include boron carbide in an amount of atleast 0.1 wt %, or at least 0.2 wt %, or at least 0.3 wt %, or at least0.4 wt %, or at least 0.5 wt %, or at least 0.6 wt %, or at least 0.7 wt%, or at least 0.75 wt %. or at least 0.8 wt %, or at least 0.9 wt %, orat least 1 wt %, or at least 1.2 wt %, or at least 1.4 wt %, or at least1.5 wt %, or at least 1.7 wt %, or at least 1.9 wt %, or at least 2 wt%, or at least 2.2 wt %, or at least 2.4 wt %, or at least 2.5 wt %, orat least 2.7 wt %, or at least 2.9 wt %, or at least 3 wt %, or at least3.2 wt %, or at least 3.4 wt %, or at least 3.5 wt %, or at least 3.7 wt%, or at least 3.9 wt %, or at least 4 wt %, or at least 4.2 wt %, or atleast 4.4 wt %, or at least 4.5 wt %, or at least 4.7 wt %, or at least4.9 wt %, or at least 5 wt %, or at least 5.2 wt %, or at least 5.5 wt%, or at least 5.7 wt %, or at least 5.9 wt %, or at least 6 wt %, or atleast 6.4 wt %, or at least 6.7 wt %, or at least 7 wt %, or at least7.2 wt %, or at least 7.5 wt %, or at least 7.7 wt %, or at least 8 wt%, or at least 8.4 wt %, or at least 8.7 wt %, or at least 9 wt %, or atleast 9.2 wt %, or at least 9.4 wt %, or at least 9.7 wt %, or at least10 wt %, based on a total weight of the first phase. Further, the firstphase can include boron carbide in a range including any of the minimumor maximum percentages noted herein. For instance, boron carbide can bepresent in the first phase in an amount including at least 0.1 wt % andat most 10 wt % for the total weight of the first phase.

The boron carbide grains in the first phase can have a certain averagegrain size that can facilitate formation and improved performance of theceramic composite. For instance, the boron carbide grains in the firstphase can have an average grain size of at least 0.3 microns, or atleast 0.5 microns, or at least 0.6 microns, or at least 0.8 microns,such as at least 0.9 microns, or at least 1 micron, or at least 1.2microns, or at least 1.5 microns, or at least 1.8 microns, or at least 2microns, or at least 2.1 microns, or at least 2.3 microns, or at least2.5 microns, or at least 2.8 microns, or at least 3 microns, or at least3.1 microns, or at least 3.3 microns, or at least 3.5 microns, or atleast 3.8 microns, or at least 3.9 microns, or at least 4.1 microns, orat least 4.3 microns, or at least 4.5 microns, or at least 4.8 microns,or at least 5 microns or at least 5.2 microns, or at least 5.5 microns,or at least 6 microns, or at least 6.3 microns, or at least 6.5 microns,or at least 7 microns, or at least 7.5 microns, or at least 8 microns,or at least 8.5 microns, or at least 9 microns, or at least 9.5 microns,or at least 9.8 microns, or at least 10 microns, or at least 12 microns,or at least 16 microns, or at least 20 microns, or at least 25 microns,or at least 30 microns, or at least 35 microns. In another instance, theboron carbide grains in the first phase can have an average grain sizeof at most 200 microns, such as at most 180 microns, at most 150microns, at most 130 microns or at most 100 microns, or at most 95microns, or at most 90 microns, or at most 85 microns, or at most 80microns, or at most 75 microns, or at most 70 microns, or at most 65microns, or at most 60, at most 55 microns, at most 50 microns, or atmost 46 microns, or at most 40 microns, or at most 35 microns, or atmost 30 microns, or at most 25 microns, or at most 20 microns, or atmost 15 microns, or at most 10 microns, or at most 8 microns, or at most6 microns, or at most 5 microns. Moreover, boron carbide grains in thefirst phase can have an average grain size in a range including any ofthe minimum and maximum values disclosed herein. For instance, boroncarbide grains in the first phase can have an average grain size in arange of 0.3 to 200 microns or in a range of 5 to 200 microns or in arange of 0.5 to 100 microns or in a range of at most 2 microns to 85microns.

Furthermore, in a particular embodiment, the first phase can includeelemental carbon in an amount of at most 7 wt %, or at most 6 wt %, orat most 5 wt %, or at most 4.5 wt %, or at most 4 wt %, or at most 3.5wt %, or at most 3 wt %, or at most 2.5 wt %, or at most 2 wt %, or atmost 1.5 wt %, or at most 1 wt %, based on a total weight of the firstphase. In another particular embodiment, the first phase can includeelemental carbon in an amount of at least 0.05 wt %, such as at least0.07 wt %, or at least 0.09 wt %, or at least 1 wt %, or at least 1.2 wt%, or at least 1.5 wt %, or at least 2 wt %, or at least 2.2 wt %, or atleast 2.5 wt %, or at least 2.8 wt %, or at least 3 wt %, or at least3.2 wt %, or at least 3.5 wt %, or at least 3.8 wt %, or at least 4 wt%, or at least 4.3 wt %, or at least 4.7 wt %, or at least 5 wt % for atotal weight of the first phase. Further, the first phase can includeelemental carbon in a range including any of the minimum or maximumpercentages noted herein. For instance, the elemental carbon can bepresent in the first phase in an amount including at least 0.05 wt % andat most 7 wt % for the total weight of the first phase.

In a further embodiment, the first phase can include elemental carbonhaving a grain size of at least 0.3 microns, such as at least 0.5microns, or at least 0.7 microns, or at least 0.9 microns, or at least 1microns, or at least 1.4 microns, or at least 1.8 microns, at least 2microns, or at least 2.5 microns, such as at least 2.7 microns, at least2.9 microns, or at least 3.5 microns, or at least 4 microns, or at least4.5 microns, or at least 5 microns, or at least 7 microns, or at least 8microns, or at least 9 microns, or at least 10 microns. In anotherembodiment, the elemental carbon in the first phase can have a grainsize of at most 100 microns, such as at most 90 microns, at most 80microns, at most 75 microns, at most 70 microns, at most 65 microns, atmost 60 microns, at most 50 microns, at most 45 microns, or at most 40microns, or at most 30 microns, or at most 25 microns, or at most 20microns, or at most 10 microns. Moreover, the elemental carbon in thefirst ceramic phase can have a grain size in a range including any ofthe minimum and maximum values noted herein. For instance, the firstceramic phase can include elemental carbon having a size in a range of0.3 to 100 microns or in a range of 0.5 microns to 80 microns.

In a particular embodiment, the first phase can include silicon carbideand boron carbide. In a more particular embodiment, silicon carbide andboron carbide can be present in the first phase in the amount noted inthis disclosure with respect to each compound. For instance, the firstphase can include silicon carbide in an amount of about 99.9 wt %, 99.8wt %, 99.75 wt %, 99.7 wt %, 99.6 wt %, 99.5 wt %, 99.4 wt %, 99.3 wt %,99.25 wt %, 99.2 wt %, 99.1 wt %, 99 wt %, 98 wt %, 97 wt %, 96 wt %, 95wt %, 94 wt %, 93 wt %, 92 wt %, 91 wt %, or 90 wt %, and ranges therebetween, and boron carbide in an amount of about 0.1 wt %, 0.2 wt %,0.25 wt %, 0.3 wt %. 0.4 wt %, 0.5 wt %, 0.6 wt %. 0.7 wt %, 0.75 wt %.0.8 wt % or 0.9 wt %, 1 wt %, 2 wt %, 3 wt %, 4 wt %, 5 wt %, 6 wt %, 7wt %, 8, wt %, 9 wt % or 10 wt %. Further, the first phase can includesilicon carbide and boron carbide in a range of any of the above valuesas minimum or maximum.

In an embodiment, the second phase can be present in the ceramiccomposite in an amount of at least 1 wt %, or at least 1.3 wt %, or atleast 2 wt %, or at least 2.5 wt %, or at least 3 wt %, or at least 4 wt%, or at least 5 wt %, or at least 6 wt %, or at least 7 wt %, or atleast 8 wt %, or at least 9 wt %, or at least 10 wt %, or at least 11 wt%, or at least 13 wt %, or at least 15 wt %, or at least 17 wt %, or atleast 18 wt %, or at least 20 wt %, or at least 22 wt %, or at least 24wt %, or at least 26 wt %, or at least 28 wt %, or at least 30 wt %, orat least 32 wt % or at least 34 wt %, or at least 36 wt %, or at least38 wt %, or at least 40 wt %, or at least 42 wt %, or at least 44 wt %,or at least 46 wt %, or at least 48 wt %, or at least 50 wt %, or atleast 52 wt %, or at least 55 wt %, or at least 58 wt %, or at least 60wt %, or at least 62 wt %, or at least 64 wt %, or at least 66 wt %, orat least 68 wt %, or at least 70 wt %, or at least 72 wt %, or at least75 wt %, or at least 78 wt %, or at least 80 wt %, or at least 82 wt %,or at least 84 wt %, or at least 86 wt %, or at least 88 wt %, or atleast 90 wt %, or at least 92 wt %, or at least 93 wt %, or at least 94wt %, or at least 96 wt %, or at least 99 wt %, based on a total weightof the ceramic composite. Further, the second phase can be present inthe ceramic composite in an amount of at most 99 wt %, at most 98 wt %,or at most 97 wt %, or at most 95 wt %, or at most 92 wt %, or at most90 wt %, or at most 88 wt %, or at most 85 wt %, or at most 82 wt %, orat most 80 wt %, or at most 78 wt %, or at most 76 wt %, or at most 74wt %, or at most 72 wt %, or at most 70 wt %, or at most 68 wt %, or atmost 66 wt %, or at most 64 wt %, or at most 62 wt %, or at most 60 wt%, or at most 58 wt %, or at most 56 wt %, or at most 54 wt %, or atmost 52 wt %, or at most 50 wt %, or at most 52 wt %, or at most 50 wt%, or at most 48 wt %, or at most 46 wt %, or at most 44 wt %, or atmost 42 wt %, or at most 40 wt %, or at most 38 wt %, or at most 36 wt%, or at most 34 wt %, or at most 32 wt %, or at most 30 wt %, or atmost 28 wt %, or at most 26 wt %, or at most 24 wt %, or at most 22 wt%, or at most 20 wt %, or at most 18 wt %, or at most 16 wt %, or atmost 14 wt %, or at most 12 wt %, or at most 10 wt %, or at most 8 wt %,or at most 6 wt %, or at most 4 wt %, or at most 3 wt %, or at most 2 wt%, or at most 1 wt %, based on a total weight of the ceramic composite.Moreover, the second phase can be present in the ceramic composite in anamount including any of the minimum and maximum percentages notedherein. For instance, the second phase can be present in the ceramiccomposite in an amount in a range of at least 1 wt % to at most 99 wt %or in a range of at least 8 wt % to at most 92 wt % or in a range of atleast 10 wt % to at most 90 wt %.

In an embodiment, the total amount of boron carbide present in theceramic composite can be at least 1 wt %, or at least 2 wt %, or atleast 3 wt %, or at least 4 wt %, or at least 5 wt %, or at least 6 wt%, or at least 7 wt %, or at least 8 wt %, or at least 9 wt %, or 10 wt%, or at least 11 wt %, or at least 13 wt %, or at least 15 wt %, or atleast 17 wt %, or at least 18 wt %, or at least 20 wt %, or at least 22wt %, or at least 24 wt %, or at least 26 wt %, or at least 28 wt %, orat least 30 wt %, or at least 32 wt % or at least 34 wt %, or at least36 wt %, or at least 38 wt %, or at least 40 wt %, or at least 42 wt %,or at least 44 wt %, or at least 46 wt %, or at least 48 wt %, or atleast 50 wt %, or at least 52 wt %, or at least 55 wt %, or at least 58wt %, or at least 60 wt %, or at least 62 wt %, or at least 64 wt %, orat least 66 wt %, or at least 68 wt %, or at least 70 wt %, or at least72 wt %, or at least 75 wt %, or at least 78 wt %, or at least 80 wt %,or at least 82 wt %, or at least 84 wt %, or at least 86 wt %, or atleast 88 wt %, or at least 90 wt %, or at least 92 wt %, or at least 93wt %, or at least 94 wt %, or at least 96 wt %, or at least 99 wt %,based on a total weight of the ceramic composite. Further, the totalamount of boron carbide present in the ceramic composite can be at most99 wt %, at most 98 wt %, or at most 97 wt %, or at most 95 wt %, or atmost 92 wt %, at most 90 wt %, or at most 88 wt %, or at most 85 wt %,or at most 82 wt %, or at most 80 wt %, or at most 78 wt %, or at most76 wt %, or at most 74 wt %, or at most 72 wt %, or at most 70 wt %, orat most 68 wt %, or at most 66 wt %, or at most 64 wt %, or at most 62wt %, or at most 60 wt %, or at most 58 wt %, or at most 56 wt %, or atmost 54 wt %, or at most 52 wt %, or at most 50 wt %, or at most 48 wt%, or at most 46 wt %, or at most 44 wt %, or at most 42 wt %, or atmost 40 wt %, or at most 38 wt %, or at most 36 wt %, or at most 34 wt%, or at most 32 wt %, or at most 30 wt %, or at most 28 wt %, or atmost 26 wt %, or at most 24 wt %, or at most 22 wt %, or at most 20 wt%, or at most 18 wt %, or at most 16 wt %, or at most 14 wt %, or atmost 12 wt %, or at most 10 wt %, or at most 9 wt %, or at most 8 wt %,or at most 6 wt %, or at most 4 wt %, or at most 2 wt %, or at most 1 wt%, based on a total weight of the ceramic composite. Moreover, the totalamount of boron carbide present in the ceramic composite can include anyof the minimum and maximum percentages noted herein. For instance, thetotal amount of boron carbide present in the ceramic composite can be ina range of at least 1 wt % to at most 99 wt % or in a range of at least10 wt % to at most 90 wt %.

In an embodiment, the second ceramic phase can include a boron carbide.In an embodiment, the second phase can include boron carbide in anamount of at least 50 wt % based on a total weight of the second phase.In another embodiment, the second phase can include greater than 50 wt %of boron carbide based on a total weight of the second phase, such as atleast 52 wt %, or at least 55 wt %, or at least 58 wt %, or at least 60wt %, or at least 63 wt %, or at least 65 wt %, or at least 67 wt %, orat least 68 wt %, or at least 70 wt %, or at least 72 wt %, or at least75 wt %, or at least 78 wt %, or at least 80 wt %, or at least 83 wt %,or at least 86 wt %, or at least 88 wt %, or at least 90 wt %, or atleast 91 wt %, or at least 92 wt %, or at least 93 wt %, or at least 94wt %, or at least 95 wt %, or at least 96 wt %, or at least 97 wt %, orat least 98 wt %, or at least 99 wt %, or at least 99.1 wt %, or atleast 99.2 wt %, or at least 99.25 wt %, or at least 99.3 wt %, or atleast 99.4 wt %, or at least 99.5 wt %, or at least 99.6 wt %, or atleast 9.7 wt %, or at least 99.75 wt %, or at least 99.8 wt %, or atleast 99.9 wt %, based on a total weight of the second phase. Further,in an embodiment, the second phase can include boron carbide in anamount of at most 99.9 wt %, or at most 99.8 wt %, or at most 99.75 wt%, or at most 99.7 wt %, or at most 99.6 wt %, or at most 99.5 wt %, orat most 99.4 wt %, or at most 99.3 wt %, or at most 99.25 wt %, or atmost 99.2 wt %, or at most 99.1 wt %, or at most 99 wt %, or at most 98wt %, or at most 97 wt %, or at most 96 wt %, or at most 95 wt %, or atmost 94 wt %, or at most 93 wt %, or at most 92 wt %, or at most 91 wt%, or at most 90 wt %, based on a total weight of the second phase. Inan embodiment, the first phase can include boron carbide in an amount ina range of any of the above minimum and maximum values. For instance,the first phase can include boron carbide in an amount in a range of 86wt % to 99.99 wt %, or 88 wt % to 99.95 wt %, or 90 wt % to 99 wt %.

In a particular embodiment, the second phase can include boron carbidehaving a certain average grain size that can facilitate improvedformation and performance of the ceramic composition. For instance, theaverage grain size of boron carbide in the second phase can be at least0.3 microns, such as at least 0.4 microns, or at least 0.5 microns, orat least 0.6 microns, or at least 0.7 microns, or at least 0.8 microns,or at least 0.9 microns, or at least 1 micron, or at least 1.2 microns,or at least 1.4 microns, or at least 1.6 microns, or at least 1.8microns, or at least 1.9 microns, or at least 2 microns, or at least 2.2microns, or at least 2.4 microns, or at least 2.6 microns, or at least2.8 microns, or at least 2.9 microns, or at least 3 microns, or at least3.2 microns, or at least 3.4 microns, or at least 3.6 microns, or atleast 3.8 microns, or at least 3.9 microns, or at least 4 microns, or atleast 4.2 microns, or at least 4.4 microns, or at least 4.6 microns, orat least 4.8 microns, or at least 5 microns, or at least 5.2 microns, orat least 5.5 microns, or at least 6 microns, or at least 6.3 microns, orat least 6.5 microns, or at least 7 microns, or at least 7.5 microns, orat least 8 microns, or at least 8.5 microns, or at least 9 microns, orat least 9.5 microns, or at least 9.8 microns, or at least 10 microns,or at least 12 microns, or at least 16 microns, or at least 20 microns,or at least 25 microns, or at least 30 microns, or at least 35 microns.In another instance, the average grain size of boron carbide in thesecond phase can be at most 200 microns, such as at most 180 microns, atmost 150 microns, at most 130 microns, or at most 100 microns, or most95 microns, or at most 90 microns, or at most 85 microns, or at most 80microns, or at most 75 microns, or at most 70 microns, or at most 65microns, or at most 60, at most 55 microns, at most 50 microns, or atmost 46 microns, or at most 40 microns, or at most 35 microns, or atmost 30 microns, or at most 25 microns, or at most 20 microns, or atmost 15 microns, or at most 10 microns, or at most 8 microns, or at most6 microns, or at most 5 microns, or at most 4.8 microns, or at most 4.6microns, or at most 4.4 microns, or at most 4.1 microns, or at most 3.9microns, or at most 3.7 microns, or at most 3.5 microns, or at most 3.3microns, or at most 3.1 microns. In a particular embodiment, the boroncarbide can have an average grain size in a range including any of theminimum and maximum values disclosed herein, such as in a range of 0.3to 200 microns, or in a range of 0.5 to 100 microns or in a range of 2to 85 microns.

In a further embodiment, the second phase can also include a siliconcarbide, a carbon, or both. In an embodiment, the second phase caninclude silicon carbide, carbon, or both, in an amount of at least 0.05wt %, or at least 0.07 wt %, or at least 0.09 wt %, or at least 0.1 wt%, or at least 0.2 wt %, or at least 0.25 wt %, or at least 0.3 wt %, orat least 0.4 wt %, or at least 0.5 wt %, or at least 0.6 wt %, or atleast 0.7 wt %, or at least 0.75 wt %, or at least 0.8 wt %, or at least0.9 wt %, or at least 1 wt %, or at least 2 wt %, or at least 3 wt %, orat least 4 wt %, or at least 5 wt %, or at least 6 wt %, or at least 7wt %, or at least 8 wt %, or at least 9 wt %, or at least 10 wt %. In anembodiment, the second phase can include silicon carbide, carbon, orboth, in an amount of at most 12 wt %, or at most 11 wt %, or at most10.5 wt %, or at most 10 wt %, at most 9 wt %, or at most 8 wt %, or atmost 7 wt %, or at most 6 wt %, or at most 5 wt %, or at most 4 wt %, orat most 3 wt %, or at most 2 wt %, or at most 1 wt %, or at most 0.9 wt%, or at most 0.8 wt %, or at most 0.7 wt %, or at most 0.6 wt %, or atmost 0.5 wt %, or at most 0.4 wt %, or at most 0.3 wt %, or at most 0.25wt %, or at most 0.2 wt %, or at most 0.1 wt %, based on the totalweight of the second phase. In an embodiment, the second phase caninclude a silicon carbide, a carbon, or both, in a range including anyof the minimum and maximum percentages noted herein, such as in a rangeof 0.05 wt % to 12 wt %, or in a range of 0.07 wt % to 11 wt %, or in arange of 0.09 to 10.5 wt %.

For example, in a particular embodiment, the silicon carbide in thesecond phase can include β-SiC. In a particular embodiment, the secondphase can include silicon carbide in an amount of at least 0.1 wt %, orat least 0.2 wt %, or at least 0.25 wt %, or at least 0.3 wt %, or atleast 0.4 wt %, or at least 0.5 wt %, or at least 0.6 wt %, or at least0.7 wt %, or at least 0.75 wt %, or at least 0.8 wt %, or at least 0.9wt %, or at least 2 wt %, or at least 3 wt %, or at least 4 wt %, or atleast 5 wt %, or at least 6 wt %, or at least 7 wt %, or at least 8 wt%, or at least 9 wt %, or at least 10 wt %, based on a total weight ofthe second phase. Further, in a particular embodiment, the second phasecan include silicon carbide in an amount of at most 10 wt %, or at most9 wt %, or at most 8 wt %, or at most 7 wt %, or at most 6 wt %, or atmost 5 wt %, or at most 4 wt %, or at most 3 wt %, or at most 2 wt %, orat most 1 wt %, based on a total weight of the second phase. Moreover,the second phase can include silicon carbide in an amount in a rangeincluding any of the minimum and maximum percentages noted herein. Forinstance, silicon carbide can be present in the second phase in anamount including at least 0.1 wt % and at most 10 wt % or in an amountincluding at least 0.5 wt % and at most 9 wt %.

In a particular embodiment, the silicon carbide grains of the secondphase can have an average grain size that can facilitate improvedformation and performance of the ceramic composite. For instance, thesilicon carbide grains of the second phase can have an average grainsize of at least 0.3 microns, such as at least 0.4 microns, or at least0.5 microns, or at least 0.6 microns, or at least 0.7 microns, or atleast 0.8 microns, or at least 0.9 microns, or at least 1 micron, or atleast 1.2 microns, or at least 1.4 microns, or at least 1.6 microns, orat least 1.8 microns, or at least 1.9 microns, or at least 2 microns, orat least 2.2 microns, or at least 2.4 microns, or at least 2.6 microns,or at least 2.8 microns, or at least 2.9 microns, or at least 3 microns,or at least 3.2 microns, or at least 3.4 microns, or at least 3.6microns, or at least 3.8 microns, or at least 3.9 microns, or at least 4microns, or at least 4.2 microns, or at least 4.4 microns, or at least4.6 microns, or at least 4.8 microns, or at least 5 microns, or at least5.2 microns, or at least 5.5 microns, or at least 6 microns, or at least6.3 microns, or at least 6.5 microns, or at least 7 microns, or at least7.5 microns, or at least 8 microns, or at least 8.5 microns, or at least9 microns, or at least 9.5 microns, or at least 9.8 microns, or at least10 microns, or at least 12 microns, or at least 16 microns, or at least20 microns, or at least 25 microns, or at least 30 microns, or at least35 microns. In another instance, the average grain size of siliconcarbide in the second phase can be at most 200 microns, at most 190microns, at most 180 microns, or at most 170 microns, or at most 150microns, or at most 140 microns, or at most 120 microns, or at most 100microns, such as at most 95 microns, or at most 90 microns, or at most85 microns, or at most 80 microns, or at most 75 microns, or at most 70microns, or at most 65 microns, or at most 60, at most 55 microns, atmost 50 microns, or at most 46 microns, or at most 40 microns, or atmost 35 microns, or at most 30 microns, or at most 25 microns, or atmost 20 microns, or at most 15 microns, or at most 10 microns, or atmost 8 microns, or at most 6 microns, at most 5 microns, or at most 4.8microns, or at most 4.6 microns, or at most 4.4 microns, or at most 4.1microns, or at most 3.9 microns, or at most 3.7 microns, or at most 3.5microns, or at most 3.3 microns, or at most 3.1 microns, or at most 2.9microns, or at most 2.6 microns, or at most 2.4 microns, or at most 2.2microns, or at most 2 microns, or at most 1.8 microns, or at most 1.5microns, or at most 1.3 microns, or at most 1 micron, or at most 0.5microns. Moreover, the grain size of silicon carbide in the second phasecan be in a range including any of the minimum and maximum values notedherein. For instance, the average grain size can be in a range of 0.3 to200 microns, or in a range of 0.8 to 200 microns, or in a range of 5microns to 200 microns.

Furthermore, in a particular embodiment, the second phase can includeelemental carbon in an amount of at most 7 wt %, or at most 6 wt %, orat most 5 wt %, or at most 4.5 wt %, or at most 4 wt %, or at most 3.5wt %, or at most 3 wt %, or at most 2.5 wt %, or at most 2 wt %, or atmost 1.5 wt %, or at most 1 wt %, based on a total weight of the secondphase. In another particular embodiment, the second phase can includeelemental carbon in an amount of at least 0.05 wt %, such as at least0.07 wt %, or at least 0.09 wt %, or at least 1 wt %, or at least 1.2 wt%, or at least 1.5 wt %, or at least 2 wt %, or at least 2.2 wt %, or atleast 2.5 wt %, or at least 2.8 wt %, or at least 3 wt %, or at least3.2 wt %, or at least 3.5 wt %, or at least 3.8 wt %, or at least 4 wt%, or at least 4.3 wt %, or at least 4.7 wt %, or at least 5 wt % for atotal weight of the second phase. Further, the second phase can includeelemental carbon in a range including any of the minimum or maximumpercentages noted herein. For instance, the elemental carbon can bepresent in the second phase in an amount including at least 0.05 wt %and at most 7 wt % for the total weight of the second phase.

In addition, the second phase can include elemental carbon having anaverage grain size of at least 0.3 microns, such as at least 0.5microns, or at least 0.7 microns, or at least 0.9 microns, or at least 1microns, or at least 1.4 microns, or at least 1.8 microns, at least 2microns, or at least 2.5 microns, such as at least 2.7 microns, at least2.9 microns, or at least 3.5 microns, or at least 4 microns, or at least4.5 microns, or at least 5 microns, or at least 7 microns, or at least 8microns, or at least 9 microns, or at least 10 microns. In anotherembodiment, the elemental carbon in the second phase can have an averagegrain size of at most 100 microns, such as at most 90 microns, at most80 microns, at most 75 microns, at most 70 microns, at most 65 microns,at most 60 microns, at most 50 microns, at most 45 microns, or at most40 microns, or at most 30 microns, or at most 25 microns, or at most 20microns, or at most 10 microns. Moreover, the elemental carbon in thesecond ceramic phase can have an average grain size in a range includingany of the minimum and maximum values noted herein. For instance, thesecond ceramic phase can include elemental carbon having a grain size inrange of 0.3 to 100 microns or in a range of 0.5 to 80 microns. Inanother embodiment, the elemental carbon in the second phase can havesimilar or different average grain size compared to the elemental carbonin the first phase.

In a further embodiment, the second phase can include silicon carbideand boron carbide. In a particular embodiment, silicon carbide and boroncarbide can be present in the second phase in the amount noted withrespect to each compound in this disclosure. For example, the secondphase can include boron carbide in an amount of about 99.9 wt %, 99.8 wt%, 99.75 wt %, 99.7 wt %, 99.6 wt %, 99.5 wt %, 99.4 wt %, 99.3 wt %,99.25 wt %, 99.2 wt %, 99.1 wt %, 99 wt %, 98 wt %, 97 wt %, 96 wt %, 95wt %, 94 wt %, 93 wt %, 92, wt %, 91 wt %, or 90 wt %, and a rangestherebetween, and silicon carbide in an amount of about 0.1 wt %, 0.2 wt%, 0.25 wt %, 0.3 wt %, 0.4 wt %, 0.5 wt %, 0.6 wt %, 0.7 wt %, 0.75 wt%, 0.8 wt %, 0.9 wt %, 1 wt %, 2 wt %, 3 wt %, 4 wt %, 5 wt %, 6 wt %, 7wt %, 8 wt %, 9 wt % or 10 wt %, or ranges therebetween. Further, thesecond phase can include silicon carbide and boron carbide in a range ofany of the above values as minimum or maximum.

In an embodiment, the ceramic composite can include a ratio of a weightpercentage of the first phase to a weight percentage of the second phasethat can facilitate improved formation of the ceramic composite. Forexample, the weight percentage ratio of the first phase to the secondphase can be at least 1:99, such as at least 2:98, or at least 5:95, orat least 8:92, or at least 10:90, at least 18:82, or at least 20:80, orat least 22:78, or at least 24:76, or at least 26:74, or at least 28:72,or at least 30:70, or at least 33:67, or at least 35:65, or at least40:60, or at least 45:55, or at least 50:50, or at least 55:45, or atleast 60:40, or at least 62:38, or at least 65:35, or at least 68:32, orat least 70:30, or at least 73:27, or at least 76:24, or at least 79:21,or at least 77:23, or at least 80:20, or at least 85:15, or at least88:12, or at least 90:10, or at least 92:8. In another embodiment, theratio of the weight percentage of the first phase to the weightpercentage of the second phase can be at most 99:1, such as at most96:4, or at most 94:6, or at most 93:7, or at most 91:9, or at most90:10, or at most 82:18, or at most 80:20, or at most 78:22, or at most76:24, or at most 74:26, or at most 72:28, or at most 70:30, or at most65:35, or at most 63:37, or at most 60:40, or at most 58:42, or at most55:45, or at most 50:50, or at most 46:54, or at most 44:56, or at most40:60, or at most 36:64, or at most 32:68, or at most 30:70, or at most25:75, or at most 23:77, or at most 20:80, or at most 18:82, or at most15:85, or at most 12:88, or at most 10:90, or at most 5:95, or at most1:99. Moreover, the ratio of the weight percentage of the first phase tothe weight percentage of the second phase can be in a range includingany of the minimum and maximum values disclosed herein, such as in arange of 1:99 to 99:1, or in a range of 5:95 to 95:5, or in a range of10:90 to 90:10, or in a range of 82:18 to 18:82, or in a range of 80:20to 20:80, or in a range of 78:22 to 22:78, or in a range of 76:24 to24:76, or in a range of 74:26 to 26:74, or in a range of 72:28 to 28:72,or in a range of 70:30 to 30:70, or in a range of 65:35 to 35:65, or ina range of 60:40 to 40:60, or in a range of 55:45 to 45:55, or in arange of 50:50, based on a total weight of the ceramic composite.

In an embodiment, as the content of the first and second phase approacheach other, such as in a range of 65:35 to 35:65, or in a range of 60:40to 40:60, or in a range of 55:45 to 45:55, or in a range of 50:50, basedon a total weight of the ceramic composite, the 3-3 connectivityappears. In another embodiment, as the content of the first and secondphase move away from each other, such as in a range of 1:99 to 99:1, orin a range of 90:10 to 10:90, or in a range of 82:18 to 18:82, or in arange of 80:20 to 20:80, or in a range of 78:22 to 22:78, or in a rangeof 76:24 to 24:76, or in a range of 74:26 to 26:74, or in a range of72:28 to 28:72, or in a range of 70:30 to 30:70, the 1-3 connectivityappears. In a further embodiment, the ceramic composite can include the3-3 connectivity, the 1-3 connectivity, or both.

In another embodiment, the ceramic composite can include a ratio of thetotal amount of silicon carbide in the ceramic composite to the totalamount of boron carbide in the ceramic composite that can facilitateimproved formation and performance. For example, the ratio of the totalamount of silicon carbide to the total amount of boron carbide can be atleast 1:99, such as at least 3:97, or at least 5:95, or at least 8:92,or at least 10:90, at least 15:85, or at least 18:82, or at least 20:80,or at least 22:38, or at least 24:76, or at least 26:74, or at least28:72, or at least 30:70, or at least 35:65, or at least 40:60, or atleast 45:55, or at least 50:50, or at least 60:40, or at least 65:35, orat least 70:30, or at least 75:25, or at least 80:20, or at least 85:15,or at least 90:10, or at least 92:8, or at least 95:5. In yet anotherembodiment, the ratio of the total amount of silicon carbide to thetotal amount of boron carbide can be at most 99:1, such as at most 95:5,or at most 92:8, or at most 90:10, or at most 86:4, or at most 82:18, orat most 80:20, or at most 78:22, or at most 76:24, or at most 74:26, orat most 72:28, or at most 70:30, or at most 65:35, or at most 60:40, orat most 55:45, or at most 50:50, or at most 45:55, or at most 40:60, orat most 35:65, or at most 30:70, or at most 25:75, or at most 20:80, orat most 15:85, or at most 10:90, or at most 8:92, or at most 5:95.Moreover, the ratio of the total amount of silicon carbide to the totalamount of boron carbide can be in a range including any of the minimumand maximum values disclosed herein, such as in a range of 1:99 to 99:1,or in a range of 5:95 to 95:5, or in a range of 10:90 to 90:10, or in arange of 82:18 to 18:82, or in a range of 80:20 to 20:80, or in a rangeof 78:22 to 22:78, or in a range of 76:24 to 24:76, or in a range of74:26 to 26:74, or in a range of 72:28 to 28:72, or in a range of 70:30to 30:70, or in a range of 65:35 to 35:65, or in a range of 60:40 to40:60, or in a range of 55:45 to 45:55, or in a range of 50:50.

In an embodiment, the ceramic composite can include a third phase. Thethird phase can include elemental carbon. In a particular embodiment,the third phase can consist essentially of elemental carbon. In anotherparticular embodiment, the third phase can have a minimum width in arange of 0.5 to 100 microns.

Further, a weight percentage of boron carbide in the first phase, basedon a total weight of the first phase, is less than a weight percentageof boron carbide in the second phase, based on a total weight of thesecond phase. Similarly, a weight percentage of silicon carbide in thesecond phase, based on a total weight of the second phase, is less thana weight percentage of silicon carbide in the first phase, based on atotal weight of the first phase.

In certain embodiments, the method for making the ceramic composite caninclude providing dry ceramic powders, dry mixing the ceramic powders,and sintering the formed mixed powders.

Conventionally, the precursor to a silicon carbide or boron carbideceramic material includes silicon carbide and boron carbide particulatesin a dispersion and wet mixed. The wet mixing is done at such highenergy, that the particulates are grinded to fine particulates havingsizes well below those described above, such as a median granule size ofno greater than 30, or 20, or 10 microns. However, in embodimentsdescribed herein, the method can include dry mixing the powder. Inparticular embodiments, the dry mixing can occur within a V-cone blenderor a double cone blender, and can be accomplished through tumbling ofthe powders within a rotating drum-type container.

The mixed powders can then be formed and sintered to achieve the ceramiccomposite described herein. In certain embodiments, as discussed abovewith respect the granulate size of the powders, the sintering caninclude pressureless sintering. As used herein, the term “pressureless”refers to ambient pressure without applying any additional pressure.

In certain embodiments, the sintering can include sintering at atemperature of at least 1900° C., or at least 2000° C., or at least2100° C. In further embodiments, the pressureless sintering can includesintering at a temperature of no greater than 4000° C., or at least3500° C., or at least 3000° C. Moreover, the pressureless sintering caninclude sintering at a temperature in a range of any of the aboveminimum and maximum values, such as in a range of 1900 to 4000° C., or2000 to 3500° C., or 2100 to 3000° C.

A particular advantage of certain embodiments of the ceramic compositehaving the multi-phasic microstructure described herein is that at leastone of the first ceramic phase and the second ceramic phase can have anaverage hardness of at least 1500 GPa, or at least 1600 GPa, or at least1700 GPa, as measured according to a Knoop Hardness Test under a 1 kgload. In further embodiments, at least one of the first ceramic phaseand the second ceramic phase can have an average hardness of at most2500 GPa, or at most 2400 GPa, or at most 2300 GPa, as measuredaccording to a Knoop Hardness Test under a 1 kg load. Moreover, at leastone of the first ceramic phase and the second ceramic phase can have anaverage hardness including any of the minimum and maximum values notedherein, as measured according to a Knoop Hardness Test under a 1 kgload. For example, at least one of the first ceramic phase and thesecond ceramic phase can have an average hardness in a range of at least1500 GPa and at most 2500 GPa.

Another particular advantage of certain embodiments of the ceramiccomposite having the multi-phasic microstructure described herein isthat the ceramic composite can have an average modulus of elasticity ofat least 360 GPa, or at least 370 GPa, or at least 380 GPa, as measuredaccording to ASTM C674-13. In further embodiments, the ceramic compositecan have an average modulus of elasticity of at most 500 GPa, or at most490 GPa, or at most 480 GPa, as measured according to ASTM C674-13.Moreover, the ceramic composite can have an average modulus ofelasticity including any of the minimum and maximum values noted herein,as measured according to ASTM C674-13. For example, the ceramiccomposite can have an average modulus of elasticity in a range of atleast 360 GPa and at most 500 GPa.

A particular advantage of certain embodiments of the ceramic compositehaving the multi-phasic microstructure described herein is that theceramic composite can have an average bulk density of at most 3.1 g/cm³,or at most 3.05 g/cm³, or at most 3 g/cm³. Further, the ceramiccomposite can have an average bulk density of at least 2.4 g/cm³, or atleast 2.5 g/cm³, or at least 2.6 g/cm³. Moreover, the ceramic compositecan have an average bulk density in a range including any of the minimumand maximum values noted herein, such as in a range of at least 2.4g/cm³ and at most 3.1 g/cm³. Bulk density can be measured by theArchimedes method weight/(weight−suspended weight) and reported ingrams/cm³.

In an embodiment, the composite can have a density of at least 95.5% ofthe theoretical density, such as at least 96.5%, at least 97%, or atleast 97.5%, or of at least 98%, or at least 98.5, or at least 99%, orat least 99.5%, or at least 99.9% of the theoretical density.

A particular advantage of certain embodiments of the ceramic compositehaving the multi-phase microstructure described herein is that theceramic composite can have an average porosity of at most 5%, or at most4%, or at most 3%. Although it may be desired to have a ceramiccomposite of 0% porosity, in many cases the ceramic composite may havean average porosity of at least 0.001%, or at least 0.01%, or at least0.1%. In a further embodiment, the ceramic composite can have an averageporosity in a range including any of the minimum and maximum percentagesdisclosed herein, such as in a range of at least 0.001% and at most 3%.Average porosity is measured by image analysis in 30 fields at >13000μ²each or >390,000μ² total.

In a further embodiment, the ceramic composite can have reduced weightcompared to a corresponding conventional ceramic product. Thecorresponding conventional ceramic product can have the same shape anddimension of the ceramic composite, but is formed with a conventionalceramic material, such as SiC. For instance, the ceramic composite canhave a weight reduction of at least 4% compared to the weight of thecorresponding conventional ceramic product, such as at least 5%, atleast 6%, at least 7%, at least 8%, at least 9%, at least 10%, at least11%, at least 12%, at least 13%, at least 14%, at least 15%, at least16%, or at least 17%. In another instance, the weight reduction can beat most 25% compared to the weight of the corresponding conventionalceramic product, such as at most 23%, at most 22%, at most 20%, at most19%, at most 18%, at most 17%, at most 16%, at most 15%, at most 14%, atmost 13%, at most 12%, at most 11%, at most 10%, at most 9%, at most 8%,at most 7%, or at most 6%. Moreover, the weight reduction can be withina range including any of the minimum and maximum percentages notedherein. The weight reduction of the ceramic composite can be determinedby the formula ΔW=(Wcon−Wcom)×100%, wherein ΔW represents the weightreduction, Wcon is the weight of the corresponding conventional ceramicproduct, and Wcom is the weight of the ceramic composite.

The ceramic composite described herein can be useful as a ceramic tile.For example, an armor subcomponent can include a ceramic tile includingthe ceramic composite described herein. The armor subcomponent caninclude a ballistic armor insert.

In accordance with an embodiment, an armor component can include aceramic body including the ceramic composite and a first componentadjacent the ceramic body. FIG. 4 includes a perspective viewillustration of an armor component 400 in accordance with an embodiment.As illustrated, the armor component 400 includes a ceramic body 401 anda first component 402. In particular instances, the first component 402may overlie the ceramic body 401. In other embodiments, it will beappreciated that the first component 402 may have a particular positionrelative to the ceramic body 401. For example, as illustrated in FIG. 5,the first component 402 may underlie the ceramic body 401. As furtherillustrated in FIG. 6, another construction of the armor component 400can include the ceramic body 401 disposed between the first component402 and a third component 403. It will be appreciated that varioussuitable arrangements of the ceramic body 401 relative to othercomponents (e.g., the first component 402 and the second component 403)are contemplated and within the scope of the embodiments describedherein. Referring to FIG. 4, in accordance with an embodiment, the firstcomponent 402 can be abutting at least a portion of the ceramic body401, and more particularly, may be in direct contact with a first majorsurface 405 of the ceramic body 401. More particularly, the firstcomponent 402 and ceramic body 401 may be bonded to each other at thefirst major surface 405 of the ceramic body 401. The opposite surface406 may be a strikeface of the ceramic body 401.

In accordance with an embodiment, the first component 401 may include aparticular material, including but not limited to a ceramic, such as aboride, a nitride, an oxide, a carbide, and any combination thereof. Inparticular, the first component 102 may include alumina (Al₂O₃), boroncarbide (B₄C), silicon carbide (SiC), calcium hexaboride (CaB₆),aluminum dodecaboride (AlB₁₂), boron suboxide (B₆O), silicon nitride(Si₃N₄), aluminum nitride (AlN), and any combination thereof. In stillanother alternative embodiment, the first component may include amaterial, such as an organic material component, and more particularly apolymer, such as a polyethylene, polyurethane, a fluorinated polymer, aresin, a thermoset, a thermoplastic, a para-aramid fiber, and anycombination thereof.

Further, it will be appreciated that the first component 401 may includea composite material, which may include a combination of materials,including for example natural materials, synthetic materials, organicmaterials, inorganic materials, and any combination thereof. Somesuitable inorganic materials can include ceramics, metals, glasses, andthe like.

In one particular embodiment, the first component 401 may include aboride material. In particular instances, the boride material mayinclude one metal element, including, for example, but not limited to, atransition metal element. In certain instances, the metal element mayinclude zirconium (Zr), titanium (Ti), aluminum (Al), and a combinationthereof. For example, the first component 102 may include calciumhexaboride (CaB₆), aluminum dodecaboride (AlB₁₂), magnesium aluminumdiboride (MgAlB₂). In one particular instance, the first component mayinclude zirconium boride (ZrB₂). In still another embodiment, the firstcomponent may include titanium boride (TiB₂).

In an alternative embodiment, the first component 401 may include acomposition, such as a first composition that is different than thecomposition of the ceramic body. For example, the first component mayinclude a first composition including a nitride material that isdifferent than a nitride material contained within the ceramic body. Thenitride material of the first component may include a metal element, inparticular a transition metal element. In particular instances, thefirst component may include silica nitride (Si₃N₄), titanium nitride(TiN), aluminium nitride (AlN), and a combination thereof.

In accordance with another embodiment, the first component may include aceramic material, including an oxide material. In certain instances, theoxide material may include aluminum oxide (Al₂O₃), boron suboxide (B₆O),and a combination thereof. In other instances, the oxide material mayinclude at least one element, including, but not limited to, atransition metal element. For example, some suitable metal elements caninclude yttrium (Y), lanthanum (La), and a combination thereof. In oneparticular instance, the first component can include an oxide materialincluding yttria (Y₂O₃). In another embodiment, the first component caninclude an oxide material comprising lanthanum oxide (La₂O₃).

In still another embodiment, the first component may include a ceramicmaterial, such as a carbide material. Suitable carbide materials mayinclude at least one metal element, including, for example, but notlimited to, a transition metal element. Some suitable transitional metalelements can include, for example, titanium (Ti), aluminum (Al), boron(B), and a combination thereof. For example, the first component mayinclude a ceramic material comprising titanium carbide (TiC). In anotherembodiment, the first component can include a carbide material includingaluminum carbide (Al₄C₃). In another embodiment, the first component mayinclude silicon carbide (SiC). In yet another embodiment, the firstcomponent may include a carbide material including boron carbide (B₄C).

In still other instances, the first component may include some naturalmaterials, for example a woven material. In other instances, the firstcomponent may include a non-woven material. Some suitable examples ofwoven and non-woven material can include those utilizing a fiber, andmore particularly, may include a ballistic fiber. In accordance with anembodiment, the ballistic fiber may include a natural material,synthetic material, and a combination thereof. According to oneparticular design, the first component may include a ballistic fiberthat includes nylon.

In another aspect, the armor component may include a second componentthat is distinct from the first component and ceramic body. In certaininstances, one or more of the ceramic body, the first component, or thesecond component may be in the form of a layer. As such, the secondcomponent can have dimensions substantially similar to the ceramic bodyand first component as described in embodiments herein. As furtherillustrated, the second component may be adjacent to the ceramiccomponent. More particularly, the second component may be overlying theceramic body. For example, the second component can be underlying theceramic body, and more particularly, may be abutting the ceramic body.It will be appreciated that the second component can have any of theattributes of the first component and the ceramic body described in theembodiments herein.

Many different aspects and embodiments are possible. Some of thoseaspects and embodiments are described below. After reading thisspecification, skilled artisans will appreciate that those aspects andembodiments are only illustrative and do not limit the scope of thepresent invention. Embodiments may be in accordance with any one or moreof the embodiments as listed below.

Embodiment 1. A ceramic composite comprising:

a first ceramic phase comprising a first ceramic material; and

a second ceramic phase comprising a second ceramic material;

wherein the first ceramic material has a different composition than thesecond ceramic material;

wherein at least one of the first ceramic phase and the second ceramicphase has a median minimum width of at least 5 microns.

Embodiment 2. A ceramic composite comprising:

a first ceramic phase comprising a first ceramic material; and

a second ceramic phase comprising a second ceramic material differentthan the first ceramic material;

wherein the ceramic composite has a modulus of elasticity of at least350 GPa, as measured according to ASTM C674-13, and each of the firstand second phases has a hardness of at least 1700 kg/mm², as measuredaccording to the Knoop hardness test under a 1 kg load.

Embodiment 3. A ceramic composite comprising:

a first ceramic material present in an amount of 35 wt % to 65 wt %,based on the total weight of the ceramic composite; and

a second ceramic material present in an amount of 35 wt % to 65 wt %,based on the total weight of the ceramic composite;

wherein the first ceramic material has a different composition than thesecond ceramic material; and

wherein the ceramic composite comprises a first phase comprising amajority of the first ceramic material and a second phase comprising amajority of the second ceramic material, the first and second phasehaving a 3-3 connectivity pattern.

Embodiment 4. A ceramic composite comprising:

a first ceramic material and a second ceramic material present in aratio of a weight percentage of the first ceramic material to a weightpercentage of the second ceramic material in a range of 82:18 to 65:35or 18:82 to 35:65;

wherein the first ceramic material has a different composition than thesecond ceramic material; and

wherein the ceramic composite comprises a first phase comprising amajority of the first ceramic material and a second phase comprising amajority of the second ceramic material, the first and second phasehaving a 1-3 connectivity pattern.

Embodiment 5. A ceramic composite comprising:

a first phase comprising a silicon carbide having a grain size in arange of 0.3 to 200 microns, or in a range of 5 to 200 microns and acarbon having a grain size in a range of 0.5 to 100 microns; and

a second phase comprising a boron carbide, a silicon carbide having agrain size in a range of 0.3 to 200 microns, and a carbon having a grainsize in range of 0.5 to 100 microns;

wherein the silicon carbide of the first phase is separated from thesilicon carbide of the second phase.

Embodiment 6. The ceramic composite of any one of embodiments 1 to 3,wherein the first phase comprises a silicon carbide.

Embodiment 7. The ceramic composite of any one of the precedingembodiments, wherein the silicon carbide of the first phase includesα-SiC, 15R—SiC, 3C—SiC, or any combination thereof.

Embodiment 8. The ceramic composite of any one of embodiments 1 to 3, 5,and 6, wherein the second phase comprises a boron carbide.

Embodiment 9. The ceramic composite of any one of the precedingembodiments, wherein the second phase further comprises a siliconcarbide including β-SiC.

Embodiment 10. The ceramic composite of any one of the precedingembodiments, wherein at least one of the first ceramic phase and thesecond ceramic phase has an average hardness of at least 1500 GPa, or atleast 1600 GPa, or at least 1700 GPa, as measured according to a KnoopHardness Test under a 1 kg load.

Embodiment 11. The ceramic composite of any one of the precedingembodiments, wherein at least one of the first ceramic phase and thesecond ceramic phase has an average hardness of at most 2500 GPa, or atmost 2400 GPa, or at most 2300 GPa, as measured according to a KnoopHardness Test under a 1 kg load.

Embodiment 12. The ceramic composite of any one of the precedingembodiments, wherein the ceramic composite has an average modulus ofelasticity of at least 360, GPa, or at least 370 GPa, or at least 380GPa, as measured according to ASTM C674-13.

Embodiment 13. The ceramic composite of any one of the precedingembodiments, wherein the ceramic composite has an average modulus ofelasticity of at most 500 GPa, or at most 490 GPa, or at most 480 GPa,as measured according to ASTM C674-13.

Embodiment 14. The ceramic composite of any one of the precedingembodiments, wherein the ceramic composite has an average bulk densityof at most 3.1 g/cm³, or at most 3.05 g/cm³, or at most 3 g/cm³.

Embodiment 15. The ceramic composite of any one of the precedingembodiments, wherein the ceramic composite has an average bulk densityof at least 2.4 g/cm³, or at least 2.5 g/cm³, or at least 2.6 g/cm³.

Embodiment 16. The ceramic composite of any one of the precedingembodiments, wherein the ceramic composite has an average porosity of atmost 5%, or at most 4%, or at most 3%.

Embodiment 17. The ceramic composite of any one of the precedingembodiments, wherein the ceramic composite has an average porosity of atleast 0.001%, or at least 0.01%, or at least 0.1%.

Embodiment 18. The ceramic composite of any one of the precedingembodiments, wherein the first phase is present in an amount of at least1 wt %, or at least 2 wt %, or at least 4 wt %, or at least 5 wt %, orat least 6 wt %, or at least 7 wt %, or at least 8 wt %, or at least 9wt %, at least 10 wt %, or at least 12 wt %, or at least 15 wt %, or atleast 18 wt %, or at least 20 wt %, or at least 22 wt %, or at least 24wt %, or at least 26 wt %, or at least 28 wt %, or at least 30 wt %, orat least 32 wt % or at least 34 wt %, or at least 36 wt %, or at least38 wt %, or at least 40 wt %, or at least 42 wt %, or at least 44 wt %,or at least 46 wt %, or at least 48 wt %, or at least 50 wt %, or atleast 52 wt %, or at least 55 wt %, or at least 58 wt %, or at least 60wt %, or at least 62 wt %, or at least 64 wt %, or at least 66 wt %, orat least 68 wt %, or at least 70 wt %, or at least 72 wt %, or at least75 wt %, or at least 78 wt %, or at least 80 wt %, or at least 82 wt %,or at least 84 wt %, or at least 86 wt %, or at least 88 wt %, or atleast 90 wt %, or at least 92 wt %, or at least 94 wt %, or at least 95wt %, or at least 97 wt %, or at least 98 wt %, or at least 99 wt %,based on a total weight of the ceramic composite.

Embodiment 19. The ceramic composite of any one of the precedingembodiments, wherein the first phase is present in an amount of at most99 wt %, at most 98 wt %, or at most 97 wt %, or at most 95 wt %, or atmost 92 wt %, at most 90 wt %, or at most 88 wt %, or at most 85 wt %,or at most 82 wt %, or at most 80 wt %, or at most 78 wt %, or at most76 wt %, or at most 74 wt %, or at most 72 wt %, or at most 70 wt %, orat most 68 wt %, or at most 66 wt %, or at most 64 wt %, or at most 62wt %, or at most 60 wt %, or at most 58 wt %, or at most 56 wt %, or atmost 54 wt %, or at most 52 wt %, or at most 50 wt %, or at most 48 wt%, or at most 46 wt %, or at most 44 wt %, or at most 42 wt %, or atmost 40 wt %, or at most 38 wt %, or at most 36 wt %, or at most 34 wt%, or at most 32 wt %, or at most 30 wt %, or at most 28 wt %, or atmost 26 wt %, or at most 24 wt %, or at most 22 wt %, or at most 20 wt%, or at most 18 wt %, or at most 16 wt %, or at most 14 wt %, or atmost 12 wt %, or at most 10 wt %, or at most 8 wt %, or at most 6 wt %,or at most 4 wt %, or at most 2 wt %, or at most 1 wt %, based on atotal weight of the ceramic composite.

Embodiment 20. The ceramic composite of any one of the precedingembodiments, wherein the second phase is present in an amount of atleast 1 wt %, or at least 1.3 wt %, or at least 2 wt %, or at least 2.5wt %, or at least 3 wt %, or at least 4 wt %, or at least 5 wt %, or atleast 6 wt %, or at least 7 wt %, or at least 8 wt %, or at least 9 wt%, or at least 10 wt %, or at least 11 wt %, or at least 13 wt %, or atleast 15 wt %, or at least 17 wt %, or at least 18 wt %, or at least 20wt %, or at least 22 wt %, or at least 24 wt %, or at least 26 wt %, orat least 28 wt %, or at least 30 wt %, or at least 32 wt % or at least34 wt %, or at least 36 wt %, or at least 38 wt %, or at least 40 wt %,or at least 42 wt %, or at least 44 wt %, or at least 46 wt %, or atleast 48 wt %, or at least 50 wt %, or at least 52 wt %, or at least 55wt %, or at least 58 wt %, or at least 60 wt %, or at least 62 wt %, orat least 64 wt %, or at least 66 wt %, or at least 68 wt %, or at least70 wt %, or at least 72 wt %, or at least 75 wt %, or at least 78 wt %,or at least 80 wt %, or at least 82 wt %, or at least 84 wt %, or atleast 86 wt %, or at least 88 wt %, or at least 90 wt %, or at least 92wt %, or at least 93 wt %, or at least 94 wt %, or at least 96 wt %, orat least 99 wt %, based on a total weight of the ceramic composite.

Embodiment 21. The ceramic composite of any one of the precedingembodiments, wherein the second phase is present in an amount of at most99 wt %, at most 98 wt %, or at most 97 wt %, or at most 95 wt %, or atmost 92 wt %, or at most 90 wt %, or at most 88 wt %, or at most 85 wt%, or at most 82 wt %, or at most 80 wt %, or at most 78 wt %, or atmost 76 wt %, or at most 74 wt %, or at most 72 wt %, or at most 70 wt%, or at most 68 wt %, or at most 66 wt %, or at most 64 wt %, or atmost 62 wt %, or at most 60 wt %, or at most 58 wt %, or at most 56 wt%, or at most 54 wt %, or at most 52 wt %, or at most 50 wt %, or atmost 52 wt %, or at most 50 wt %, or at most 48 wt %, or at most 46 wt%, or at most 44 wt %, or at most 42 wt %, or at most 40 wt %, or atmost 38 wt %, or at most 36 wt %, or at most 34 wt %, or at most 32 wt%, or at most 30 wt %, or at most 28 wt %, or at most 26 wt %, or atmost 24 wt %, or at most 22 wt %, or at most 20 wt %, or at most 18 wt%, or at most 16 wt %, or at most 14 wt %, or at most 12 wt %, or atmost 10 wt %, or at most 8 wt %, or at most 6 wt %, or at most 4 wt %,or at most 3 wt %, or at most 2 wt %, or at most 1 wt %, based on atotal weight of the ceramic composite.

Embodiment 22. The ceramic composite of any one of the precedingembodiments, wherein a ratio of a weight percentage of the first phaseto a weight percentage of the second phase is in a range of 1:99 to99:1, or in a range of 5:95 to 95:5, or in a range of 10:90 to 90:10, orin a range of 82:18 to 18:82, or in a range of 80:20 to 20:80, or in arange of 78:22 to 22:78, or in a range of 76:24 to 24:76, or in a rangeof 74:26 to 26:74, or in a range of 72:28 to 28:72, or in a range of70:30 to 30:70, or in a range of 65:35 to 35:65, 60:40 to 40:60, or in arange of 55:45 to 45:55, or in a range of 50:50, based on a total weightof the ceramic composite.

Embodiment 23. The ceramic composite of any one of the precedingembodiments, wherein a weight percentage of silicon carbide in the firstphase, based on a total weight of the first phase, is greater than aweight percentage of silicon carbide in the second phase, based on atotal weight of the second phase.

Embodiment 24. The ceramic composite of any one of the precedingembodiments, wherein the first phase includes silicon carbide in anamount of at least 50 wt %, or at least 52 wt %, or at least 55 wt %, orat least 58 wt %, or at least 60 wt %, or at least 62 wt %, or at least64 wt %, or at least 66 wt %, or at least 68 wt %, or at least 70 wt %,or at least 72 wt %, or at least 75 wt %, or at least 78 wt %, or atleast 80 wt %, or at least 82 wt %, or at least 84 wt %, or at least 86wt %, or at least 88 wt %, or at least 90 wt %, or at least 91 wt %, orat least 92 wt %, or at least 93 wt %, or at least 94 wt %, or at least95 wt %, or at least 96 wt %, or at least 97 wt %, or at least 98 wt %,or at least 99 wt %, or at least 99.1 wt %, or at least 99.2 wt %, or atleast 99.25 wt %, or at least 99.3 wt %, or at least 99.4 wt %, or atleast 99.5 wt %, or at least 99.6 wt %, or at least 99.7 wt %, or atleast 99.75 wt %, or at least 99.8 wt %, or at least 99.9 wt %, based ona total weight of the first phase.

Embodiment 25. The ceramic composite of any one of the precedingembodiments, wherein the first phase includes silicon carbide in anamount of at most 99.9 wt %, or at most 99.8 wt %, or at most 99.75 wt%, or at most 99.7 wt %, or at most 99.6 wt %, or at most 99.5 wt %, orat most 99.4 wt %, or at most 99.3 wt %, or at most 99.25 wt %, or atmost 99.2 wt %, or at most 99.1 wt %, or at most 99 wt %, or at most 98wt %, or at most 97 wt %, or at most 96 wt %, or at most 95 wt %, or atmost 94 wt %, or at most 93 wt %, or at most 92 wt %, or at most 91 wt%, or at most 90 wt %, based on a total weight of the first phase.

Embodiment 26. The ceramic composite of any one of the precedingembodiments, wherein the second phase includes boron carbide in anamount of at least 50 wt %, or at least 52 wt %, or at least 55 wt %, orat least 58 wt %, or at least 60 wt %, or at least 62 wt %, or at least64 wt %, or at least 66 wt %, or at least 68 wt %, or at least 70 wt %,or at least 72 wt %, or at least 75 wt %, or at least 78 wt %, or atleast 80 wt %, or at least 82 wt %, or at least 84 wt %, or at least 86wt %, or at least 88 wt %, or at least 90 wt %, or at least 91 wt %, orat least 92 wt %, or at least 93 wt %, or at least 94 wt %, or at least95 wt %, or at least 96 wt %, or at least 97 wt %, or at least 98 wt %,or at least 99 wt %, %, or at least 99.1 wt %, or at least 99.2 wt %, orat least 99.25 wt %, or at least 99.3 wt %, or at least 99.4 wt %, or atleast 99.5 wt %, or at least 99.6 wt %, or at least 99.7 wt %, or atleast 99.75 wt %, or at least 99.8 wt %, or at least 99.9 wt %, based ona total weight of the second phase.

Embodiment 27. The ceramic composite of any one of the precedingembodiments, wherein the second phase includes boron carbide in anamount of at most 99.9 wt %, or at most 99.8 wt %, or at most 99.75 wt%, or at most 99.7 wt %, or at most 99.6 wt %, or at most 99.5 wt %, orat most 99.4 wt %, or at most 99.3 wt %, or at most 99.25 wt %, or atmost 99.2 wt %, or at most 99.1 wt %, or at most 99 wt %, or at most 98wt %, or at most 97 wt %, or at most 96 wt %, or at most 95 wt %, or atmost 94 wt %, or at most 93 wt %, or at most 92 wt %, or at most 91 wt%, or at most 90 wt %, based on a total weight of the second phase.

Embodiment 28. The ceramic composite of any one of the precedingembodiments, wherein a weight percentage of boron carbide in the firstphase, based on a total weight of the first phase, is less than a weightpercentage of boron carbide in the second phase, based on a total weightof the second phase.

Embodiment 29. The ceramic composite of any one of the precedingembodiments, wherein the first phase includes boron carbide in an amountof at most 10 wt %, such as at most 9.8 wt %, or at most 9.5 wt %, or atmost 9.2 wt %, or at most 9 wt %, or at most 8.8 wt %, or at most 8.5 wt%, or at most 8.2 wt %, or at most 8 wt %, or at most 7.8 wt %, or atmost 7.5 wt %, or at most 7.3 wt %, or at most 7.2 wt %, or at most 7 wt%, at most 6.8 wt %, or at most 6.5 wt %, or at most 6.3 wt %, or atmost 6 wt %, or at most 5.8 wt %, or at most 5.5 wt %, or at most 5.2 wt%, or at most 5 wt %, or at most 4.8 wt %, or at most 4.5 wt %, or atmost 4.2 wt %, or at most 4 wt %, or at most 3.8 wt %, or at most 3.5 wt%, or at most 3.2 wt %, or at most 3 wt %, or at most 2.8 wt %, or atmost 2.5 wt %, or at most 2.2 wt %, or at most 2 wt %, or at most 1.8 wt%, or at most 1.5 wt %, or at most 1.2 wt %, or at most 1 wt %, or atmost 0.9 wt %, or at most 0.8 wt %, or at most 0.7 wt %, or at most 0.6wt %, or at most 0.5 wt %, or at most 0.4 wt %, or at most 0.3 wt %, orat most 0.25 wt %, or at most 0.2 wt %, or at most 0.1 wt %, based on atotal weight of the first phase.

Embodiment 30. The ceramic composite of any one of the precedingembodiments, wherein the first phase includes boron carbide in an amountof at least 0.1 wt %, or at least 0.2 wt %, or at least 0.3 wt %, or atleast 0.4 wt %, or at least 0.5 wt %, or at least 0.6 wt %, or at least0.7 wt %, or at least 0.75 wt %. or at least 0.8 wt %, or at least 0.9wt %, or at least 1 wt %, or at least 1.2 wt %, or at least 1.4 wt %, orat least 1.5 wt %, or at least 1.7 wt %, or at least 1.9 wt %, or atleast 2 wt %, or at least 2.2 wt %, or at least 2.4 wt %, or at least2.5 wt %, or at least 2.7 wt %, or at least 2.9 wt %, or at least 3 wt%, or at least 3.2 wt %, or at least 3.4 wt %, or at least 3.5 wt %, orat least 3.7 wt %, or at least 3.9 wt %, or at least 4 wt %, or at least4.2 wt %, or at least 4.4 wt %, or at least 4.5 wt %, or at least 4.7 wt%, or at least 4.9 wt %, or at least 5 wt %, or at least 5.2 wt %, or atleast 5.5 wt %, or at least 5.7 wt %, or at least 5.9 wt %, or at least6 wt %, or at least 6.4 wt %, or at least 6.7 wt %, or at least 7 wt %,or at least 7.2 wt %, or at least 7.5 wt %, or at least 7.7 wt %, or atleast 8 wt %, or at least 8.4 wt %, or at least 8.7 wt %, or at least 9wt %, or at least 9.2 wt %, or at least 9.4 wt %, or at least 9.7 wt %,or at least 10 wt %, based on a total weight of the first phase.

Embodiment 31. The ceramic composite of any one of the precedingembodiments, wherein the second phase includes silicon carbide in anamount of at least 0.1 wt %, or at least 0.2 wt %, or at least 0.25 wt%, or at least 0.3 wt %, or at least 0.4 wt %, or at least 0.5 wt %, orat least 0.6 wt %, or at least 0.7 wt %, or at least 0.75 wt %, or atleast 0.8 wt %, or at least 0.9 wt %, or at least 2 wt %, or at least 3wt %, or at least 4 wt %, or at least 5 wt %, or at least 6 wt %, or atleast 7 wt %, or at least 8 wt %, or at least 9 wt %, or at least 10 wt%, based on a total weight of the second phase.

Embodiment 32. The ceramic composite of any one of the precedingembodiments, wherein the second phase includes silicon carbide in anamount of at most 10 wt %, or at most 9 wt %, or at most 8 wt %, or atmost 7 wt %, or at most 6 wt %, or at most 5 wt %, or at most 4 wt %, orat most 3 wt %, or at most 2 wt %, or at most 1 wt %, based on a totalweight of the second phase.

Embodiment 33. The ceramic composite of any one of the precedingembodiments, wherein the first phase, second phase, or both, includeselemental carbon in an amount of at most 7 wt %, or at most 6 wt %, orat most 5 wt %, or at most 4.5 wt %, or at most 4 wt %, or at most 3.5wt %, or at most 3 wt %, or at most 2.5 wt %, or at most 2 wt %, or atmost 1.5 wt %, or at most 1 wt %, based on a total weight of therespective phase or phases.

Embodiment 34. The ceramic composite of any one of the precedingembodiments, wherein the first phase, second phase, or both, has aminimum width in a range of 1 to 200 micron.

Embodiment 35. The ceramic composite of any one of the precedingembodiments, wherein the carbon phase having a minimum width in a rangeof 0.5 to 100 microns.

Embodiment 36. The ceramic composite of any one of the precedingembodiments, wherein the first phase includes silicon carbide grainshaving a grain size in a range of 1 to 150 microns.

Embodiment 37. The ceramic composite of any one of the precedingembodiments, wherein the first phase includes boron carbide grainshaving a grain size in a range of 5 to 200 microns.

Embodiment 38. The ceramic composite of any one of the precedingembodiments, wherein the second phase include boron carbide grains andsilicon carbide grains, each having a grain size in a range of 5 to 200microns.

Embodiment 39. The ceramic composite of any one of the precedingembodiments, wherein the first phase, second phase, or both, includeselemental carbon grains having a grain size in a range of 0.5 to 100microns.

Embodiment 40. A method of making the ceramic composite of any one ofthe preceding embodiments comprising dry blending a first phaseprecursor powder and a second phase precursor powder and sintering themixture of precursor powders.

Embodiment 41. The method of embodiment 39, wherein sintering themixture includes pressureless sintering.

Embodiment 42. The method of embodiment 40, wherein the pressurelesssintering includes sintering at a temperature of at least 1900° C., orat least 2000° C., or at least 2100° C.

Embodiment 43. A ceramic body comprising the ceramic composite of anyone of embodiments 1 to 39.

Embodiment 44. An armor subcomponent comprising the ceramic tile ofembodiment 39.

Embodiment 45. An armor component comprising a ceramic body and a firstcomponent adjacent the ceramic body, the ceramic body comprising theceramic composite of any one of embodiments 1 to 39.

EXAMPLE Example 1

Representative ceramic composite plates, S1 to S9, were formed inaccordance with embodiments herein. Silicon carbide and boron carbidewere dry mixed at the weight percent ratios included in Table 1.Corresponding conventional plates, C1, were formed with silicon carbide.

TABLE 1 SiC:B₄C S1 80:20 S2 70:30 S3 65:35 S4 60:40 S5 50:50 S6 40:60 S735:65 S8 30:70 S9 20:80

FIGS. 7A to 7C include scanning electronic microscopic images of S2, S5,and S8, respectively. Ballistic testing is to be performed on samples S1to S9. One or more of samples S1 to S9 are expected to perform well in avariety of standardized armor ballistic tests, such as those performedin accordance with ASTM Ballistic Standards, Federal RailroadAdministration FRA Ballistic Standards, MIL-SAMIT Ballistic Standards,National Institute of Justice (NIT) Ballistic Standards, Statedepartment (SD) Ballistic Standards, or European Standard EN 1063, withor without minor modifications. One of more of S1 to S9 samples areexpected to demonstrate notably improved performance in thwartingmultiple shots using different types of projectiles compared toconventional samples.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed is not necessarily the order inwhich they are performed.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

The specification and illustrations of the embodiments described hereinare intended to provide a general understanding of the structure of thevarious embodiments. The specification and illustrations are notintended to serve as an exhaustive and comprehensive description of allof the elements and features of apparatus and systems that use thestructures or methods described herein. Separate embodiments may also beprovided in combination in a single embodiment, and conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, reference to values stated in ranges can include each and everyvalue within that range. Many other embodiments may be apparent toskilled artisans only after reading this specification. Otherembodiments may be used and derived from the disclosure, such that astructural substitution, logical substitution, or another change may bemade without departing from the scope of the disclosure. Accordingly,the disclosure is to be regarded as illustrative rather thanrestrictive.

What is claimed is:
 1. A ceramic composite comprising: a first ceramicphase comprising grains of a first ceramic material; and a secondceramic phase comprising grains of a second ceramic material; wherein:the first ceramic material has a different composition than the secondceramic material; at least one of the first ceramic phase and the secondceramic phase has a median minimum width of at least 5 microns; and thefirst phase, second phase, or both, includes grains of element carbon,wherein the elemental carbon is in an amount of at most 7 wt %, based ona total weight of the respective phase or phases.
 2. The ceramiccomposite of claim 1, the first ceramic material includes siliconcarbide grains having an average grain size in a range of 0.3 to 200microns.
 3. The ceramic composite of claim 1, wherein the second ceramicmaterial comprises boron carbide grains having an average grain size ina range of 0.3 microns to 100 microns.
 4. The ceramic composite of claim1, wherein the ceramic composite is a diphasic composite.
 5. The ceramiccomposite of claim 1, wherein the first and second ceramic phases have a3-3 connectivity pattern, a 1-3 connectivity pattern, or both.
 6. Theceramic composite of claim 1, wherein the first ceramic materialcomprises silicon carbide including αSiC, 15R—SiC, 3C—SiC, or anycombination thereof.
 7. The ceramic composite of claim 1, wherein theceramic composite has a modulus of elasticity of at least 350 GPa and atmost 500 GPa.
 8. The ceramic composite of claim 1, wherein the ceramiccomposite has an average bulk density of at least 2.4 g/cm³ and at most3.1 g/cm³.
 9. The ceramic composite of claim 1, wherein the ceramiccomposite has an average porosity of at most 5%.
 10. An armor componentcomprising a ceramic body including the ceramic composite of claim 1 anda first component adjacent the ceramic body.
 11. A ceramic compositecomprising: a first phase comprising grains of a silicon carbide havingan average grain size in a range of 0.3 to 200 microns and grains of anelemental carbon having an average grain size in a range of 0.5 to 100microns; and a second phase comprising grains of a boron carbide andgrains of an elemental carbon, the grains of the elemental carbon havingan average grain size in range of 0.5 to 100 microns.
 12. The ceramiccomposite of claim 11, wherein the second phase comprises the grains ofthe boron carbide having an average grain size of 0.3 to 100 microns.13. The ceramic composite of claim 11, wherein the first phase, secondphase, or both, has a median minimum width in a range of 5 to 200microns.
 14. The ceramic composite of claim 11, wherein silicon carbideis present in an amount of at least 1 wt % and at most 99 wt % for atotal weight of the ceramic composite.
 15. The ceramic composite ofclaim 11, wherein boron carbide is present in an amount of at least 1 wt% and at most 99 wt % for the total weight of the ceramic composite. 16.The ceramic composite of claim 11, further comprising a ratio of weightpercentage of silicon carbide for a total weight of the ceramiccomposite to a weight percentage of boron carbide for the total weightof the ceramic composite in a range of 1:99 to 99:1.
 17. The ceramiccomposite of claim 11, wherein the first phase comprises silicon carbidein an amount of at least 86 wt % and at most 99.9 wt %, based on a totalweight of the first phase.
 18. The ceramic composite of claim 17,wherein the first phase further comprises grains of boron carbide. 19.The ceramic composite of claim 11, wherein the second phase comprisesboron carbide in an amount of at least 86 wt % and at most 99.9 wt %,based on a total weight of the second phase.
 20. The ceramic compositeof claim 19, wherein the second phase further comprises grains ofsilicon carbide, wherein the grains of the silicon carbide of the firstphase is separated from grains of the silicon carbide of the secondphase.